This invention relates to chairs, and more particularly, to a stackable, ergonomic chair with a mesh back and seat.
It is generally known to make chairs with backs and seats comprising mesh supporting surfaces comprised of yieldable resilient surfaces that deflect when sat upon. It is believed that such chairs are more comfortable than chairs made with solid seats and backs since they more easily conform to the shape of the body of a seated person.
A typical chair having such characteristics is disclosed in Stumpf et al., U.S. Pat. No. 6,059,368.
However, it has not been generally recognized that a better sitting experience can be achieved by maximizing the transverse distance of the mesh supporting surface relative to the body of the seated person.
Further, it has not been generally recognized that varying the resistance to deflection of different parts of the mesh supporting surface when person sits on the chair in accordance with the weight that it will bear during seating will minimize muscle fatigue and will minimize interference with blood circulation through the lower back and legs.
Accordingly, it would be advantageous to provide an ergonomic chair having a mesh support surface where different parts of the mesh have different resistance to deflection in accordance with the load that they will have to support when a person sits on the chair.
It would be additionally beneficial if the mesh supporting surface were supported by that outer periphery of a frame having a central opening so that when the mesh supporting surface is deflected, it does not touch the other parts of the frame.
With the foregoing in mind, the invention relates to an ergonomic chair that includes a frame that has outer and inner peripheries and an upper surface. A mesh supporting surface for supporting a portion of a body of a person is provided. The mesh supporting surface is supported on the outer periphery of said frame. It is comprised of a yieldable resilient material which deflects to at least a first predetermined angle when supporting a portion of the body of a person. The inner periphery of the frame is disposed below the angle of deflection of the mesh so that the mesh does not engage the inner periphery when it supports a portion of the body of a person.
In another aspect of the invention the mesh supporting surface is comprised of transverse fibers which are normally under tension and some of said fibers are under more tension than other fibers to reduce their deflection under load.